1. Field of the Invention
The present invention relates to a method and an apparatus for manufacturing an electronic circuit board, and particularly to a technology for correcting short-circuit defect of an electronic circuit board on which repeated wirings and electrode patterns are formed.
2. Description of the Related Art
Currently, there is a heavy demand for cost reduction of a liquid crystal display panel with expansion of its market. On the other hand, the size of a glass substrate required for the manufacture of the liquid crystal display panel becomes larger and larger every year. In this situation, it is difficult to produce such a liquid crystal display panel causing no short-circuit defect only by process improvement, which is one of the major reasons for cost increase. Thus, a step for correcting this defect is currently needed.
The liquid crystal display panel includes a thin film transistor substrate (TFT substrate) on which pixel circuits, driving circuits and the like are provided, a color filter substrate (opposed substrate) on which red, blue, and green resin films and the like are disposed in matrix, and liquid crystals sandwiched between the TFT substrate and the opposed substrate. Pattern defect produced on the color filter or the circuit causes display abnormality, and the liquid crystal display panel containing display abnormality becomes an inferior product. Examples of display abnormality includes coloring defect caused by entrance of resin applied to the color filter into adjacent pixels, application unevenness caused by non-uniform thickness of resin film, short-circuit and disconnection of circuits containing wirings, electrodes and the like, and others. Particularly, the short-circuit defect of the circuit can be easily corrected by cutting only the wire or electrode corresponding to the short-circuit, and a preferable product can be easily produced.
For example, a cutting method by applying laser beam to the short-circuit portion based on defect coordinates detected by an inspection device, and a removing method by using a micro-manipulator are known as technology for correcting the short-circuit defect of the circuit. There is also an automatic correction technology for automatically identifying the detect portion based on defect coordinates and defect image detected by an optical inspection device, and removing the defect portion by using cutting patterns set in advance. JP-A-2000-208902 discloses an example of this automatic correction technology.